Ernie Ball 2923 M-Steel Super Slinky Electric Guitar StringsErnie Ball M Steel Electric Guitar Strings M Steels are made of a patented Super Cobalt alloy wrapped around a Maraging steel hex core wire, producing a richer and fuller tone with a powerful low end response. M Steel plain electric guitar strings are comprised of a specially tempered steel for maximum fatigue resistance. The electric plain strings also utilize a patented winding of steel around the ball end that reduces slippage, breakage and stays